uaudio_configure_msg
struct uaudio_softc *sc = ((struct uaudio_configure_msg *)pm)->sc;
struct uaudio_configure_msg sc_config_msg[2];
static usb_proc_callback_t uaudio_configure_msg;
sc->sc_config_msg[0].hdr.pm_callback = &uaudio_configure_msg;
sc->sc_config_msg[1].hdr.pm_callback = &uaudio_configure_msg;